Gulf of Tadjoura, East Africa: NASA space-shuttle photograph, STS052-153-212, 11/01/92, 5-inch format. Near-vertical view, east toward top. The Gulf of Tadjoura is an extension of the sea-floor spreading zone in the Gulf of Aden. The volcanic rift zone is propagating westward into African continental crust. Lake Asal (just left of center) is part of this active rift system, 155 m below sea level.